Digital Photography Review
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| Nikon Coolpix 2500 | Minolta DiMAGE X |
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| Canon Digital IXUS 300 (S300 ELPH) | Nikon Coolpix 775 |
In the table below we're only measuring colour. The RGB values were measured from a VGA reduced image (to average colours, remove noise and eliminate JPEG artifacts) using the Eyedropper tool in Photoshop with a 5 by 5 Average Sample Size.
| Patch | Nikon Coolpix 2500 |
Minolta DiMAGE X |
Canon
Digital IXUS 300 (S300) |
Nikon Coolpix 775 |
| Black | 27,27,27 | 17,18,18 | 21,21,21 | 16,20,19 |
| Middle Gray |
100,101,103 |
94,93,92 |
98,98,98 |
97,98,98 |
| White | 207,208,208 | 208,209,207 | 213,213,209 | 202,204,200 |
| Magenta | 219,39,123 | 206,35,81 | 204,38,112 | 219,31,83 |
| Red | 209,32,41 | 198,30,25 | 201,30,40 | 212,17,9 |
| Yellow | 209,197,15 | 217,196,65 | 206,193,31 | 187,189,39 |
| Green | 0,143,55 | 0,143,94 | 25,131,63 | 0,156,77 |
| Cyan |
4,161,207 |
0,155,229 |
30,155,209 |
0,186,214 |
| Blue |
58,47,124 |
43,39,76 |
24,30,93 |
26,41,100 |
The Coolpix 2500 produced a very pleasing and accurate colour balance in our tests, notably it has a much lighter black and middle gray than the Coolpix 775. This can also be seen in sample shots which do have better defined and more visible shadow detail.
Resolution Comparison
Shots here are of the PIMA/ISO 12233 standard resolution test chart (more of which are available in our comparison database). This resolution chart allows us to measure the actual performance of the lens and sensor system. It measures the ability of the camera to resolve lines at gradually higher resolutions and enables us to provide a definitive value for comparison purposes. Values on the chart are 1/100th lines per picture height. So a value of 8 equates to 800 lines per picture height.
Studio light, cameras set to auto, all settings factory default. Exposure compensation +0.7 EV for all cameras.
| Horizontal resolution | Vertical resolution | 5 degree diagonal res. |
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| Nikon Coolpix 2500 | ||
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| Minolta DiMAGE X | ||
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| Canon Digital IXUS 300 (S300 ELPH) | ||
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| Nikon Coolpix 775 | ||
Measurable findings (three measurements taken for each camera):
| Camera | Measurement | Absolute Res. | Extinction Res. |
| Nikon Coolpix 2500 | Horiz LPH | 750 | * 1000 |
| Vert LPH | 750 | 1000 | |
| 5° Diagonal LPH | 800 | 900 | |
| Minolta DiMAGE X | Horiz LPH | 750 | * 900 |
| Vert LPH | 700 | * 1100 | |
| 5° Diagonal LPH | 700 | 900 | |
| Canon Digital IXUS 300 | Horiz LPH | 820 | *1000 |
| Vert LPH | 800 | 1050 | |
| 5° Diagonal LPH | 800 | 900 | |
| Nikon Coolpix 775 | Horiz LPH | 750 | * 950 |
| Vert LPH | 750 | 1000 | |
| 5° Diagonal LPH | 800 | 900 |
* Moiré is visible
Definition of terms:
| LPH | Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical) |
| 5° Diagonal | Lines set at 5° diagonal |
| Absolute Resolution | Still defined detail (below Nyquist frequency*) |
| Extinction Resolution | Detail beyond camera's definition (becomes a solid gray alias) |
| n/a | Not Available (above the capability of the test chart) |
| n/v | Not Visible (not visible on test results) |
image detail. Beyond the Nyquist frequency aliasing occurs.
An average performance from Nikon's latest two megapixel Coolpix. We really expected it to have much more resolution than the 775, certainly as much as the Canon Digital IXUS 300 (S300). Unfortunately this wasn't the case. The other very noticeable thing about the 2500's vertical resolution are the clearly visible strong moiré patterns.
From:
http://www.dpreview.com/reviews/NikonCP2500/
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